[Clinical and laboratory studies on four Chinese patients with succinate-CoA ligase deficiency noticed by mild methylmalonic aciduria]

OBJECTIVE

To study the clinical and genetic features of the patients with secondary methylmalonic aciduria due to succinate-CoA ligase deficiency.

METHOD

From February 2011 to April 2014, 4 Chinese patients with succinate-CoA ligase deficiency and mild methylmalonic aciduria were enrolled in this study. The clinical course, biochemical features, brain MRI findings, and mutations were analyzed.

RESULT

Four patients presented with severe psychomotor retardation, hypotonia, seizures, feeding problems and failure to thrive from the age of one day to 6 months. Three of them had intractable epilepsies. One had hearing defect. Mild methylmalonic aciduria was detected by elevated urine methylmalonic acid and blood propionylcarnitine at the age of 6 months to 2 years and 8 months. Five mutations, c. 550G>A, c. 751C>T, c. 809A>C, c. 961C>G and c. 826-2A>G in SUCLG1 of three patients were identified. On SUCLA2, one novel mutation, c. 970C>T, was found in one patient. After treatment, the disease in all four patients was improved.

CONCLUSION

Four Chinese patients with succinyl-CoA ligase deficiency caused by SUCLG1 and SUCLA2 mutations were noticed by mild methylmalonic aciduria and diagnosed using high-throughput genomic sequencing. Succinate-CoA ligase deficiency is a rare cause of methylmalonic aciduria. Biochemical and gene studies are necessary for the differential diagnoses.

[The effect of CPAP therapy on dizziness]

Objective:To implore the effect of continuous positive airway pressure (CPAP) therapy on dizziness patients and its mechanism. Method:Seventy-five dizziness patients were enrolled. All patients accepted polysomnographic test, dizziness handicap inventory, Pitsburgh sleep quality index and Epworth sleepiness scale before and after CPAP therapy. Patients were divided into two groups according to a polysomnographic test: OSAHS group (AHI≥15) and without OSAHS group (AHI<15); divided into three groups according to dizziness handicap inventory score: mild dizziness group (0<DHI≤30), moderate dizziness group (30<DHI≤60), severe dizziness group (60<DHI≤100); divided into three groups according to therapy time: 0-<3 months group, 3-<6 months group, 6-12 months group; divided into four groups according to age: youngth group (age<45), middle age group (45-<60), younger old group (60-<75) and old group (≥75). Result:①There was a significant difference in all dizziness patients before and after CPAP therapy according DHI (P<0.01). ②The effectiveness of CPAP therapy between OSAHS group and without OSAHS group has no difference (P>0.05), but CPAP therapy could ameliorate sleep disorder of the OSAHS group. ③Different levels of dizziness had no impact on improving DHI during CPAP therapy. However, the effect on sleep improvement decreased when patients had heavier dizziness. ④Treating by CPAP after three months could significantly improve patients dizziness (P<0.01). ⑤The dizziness of the patients in younger old group and old group have significant improvement after CPAP therapy (P<0.01). However, only younger old group has better sleep. Conclusion:CPAP therapy could dramatically improve dizziness in patients with sleep disorders.

Simultaneous detection of papaya ringspot virus, papaya leaf distortion mosaic virus, and papaya mosaic virus by multiplex real-time reverse transcription PCR

Both the single infection of papaya ringspot virus (PRSV), papaya leaf distortion mosaic virus (PLDMV) or papaya mosaic virus (PapMV) and double infection of PRSV and PLDMV or PapMV which cause indistinguishable symptoms, threaten the papaya industry in Hainan Island, China. In this study, a multiplex real-time reverse transcription PCR (RT-PCR) was developed to detect simultaneously the three viruses based on their distinctive melting temperatures (Tms): 81.0±0.8°C for PRSV, 84.7±0.6°C for PLDMV, and 88.7±0.4°C for PapMV. The multiplex real-time RT-PCR method was specific and sensitive in detecting the three viruses, with a detection limit of 1.0×10(1), 1.0×10(2), and 1.0×10(2) copies for PRSV, PLDMV, and PapMV, respectively. Indeed, the reaction was 100 times more sensitive than the multiplex RT-PCR for PRSV, and 10 times more sensitive than multiplex RT-PCR for PLDMV. Field application of the multiplex real-time RT-PCR demonstrated that some non-symptomatic samples were positive for PLDMV by multiplex real-time RT-PCR but negative by multiplex RT-PCR, whereas some samples were positive for both PRSV and PLDMV by multiplex real-time RT-PCR assay but only positive for PLDMV by multiplex RT-PCR. Therefore, this multiplex real-time RT-PCR assay provides a more rapid, sensitive and reliable method for simultaneous detection of PRSV, PLDMV, PapMV and their mixed infections in papaya.

Comparative ultrastructure of pretarsi in five calyptrate species

Pretarsi are the most important structures that allow flies to walk on various smooth surfaces and act as contact sensory organs. The pretarsal ultrastructure, including adhesive pads, claws, unguitractors, and bristles, of five calyptrate species are presented and described in detail, including Calliphora calliphoroides (Rohdendorf, 1931), Lucilia sericata (Meigen, 1826), Sarcophaga portschinskyi (Rohdendorf, 1937), Muscina stabulans (Fallen, 1817) and Portschinskia magnifica Pleske, 1926. Two types of tenent setae (spoon-tipped and spatula-tipped) are present on the ventral side of pulvilli in all species. The density of tenent setae and the pulvilli area in forelegs, midlegs, and hindlegs of both sexes are different. Among the five species, Ca. calliphoroides has unusually large pulvilli to its body size. These results provide morphological details that help to understand the movement and attachment of flies.

Squeezed light from a diamond-turned monolithic cavity

For some crystalline materials, a regime can be found where continuous ductile cutting is feasible. Using precision diamond turning, such materials can be cut into complex optical components with high surface quality and form accuracy. In this work we use diamond-turning to machine a monolithic, square-shaped, doubly-resonant LiNbO3 cavity with two flat and two convex facets. When additional mild polishing is implemented, the Q-factor of the resonator is found to be limited only by the material absorption loss. We show how our monolithic square resonator may be operated as an optical parametric oscillator that is evanescently coupled to free-space beams via birefringent prisms. The prism arrangement allows for independent and large tuning of the fundamental and second harmonic coupling rates. We measure 2.6 ± 0.5 dB of vacuum squeezing at 1064 nm using our system. Potential improvements to obtain higher degrees of squeezing are discussed.

Background removal in soil analysis using laser- induced breakdown spectroscopy combined with standard addition method

The matrix effect of powder samples, especially for soil samples, is significant in laser-induced breakdown spectroscopy (LIBS), which affects the prediction accuracy of the element concentration. In order to reduce this effect of the soil samples in LIBS, the standard addition method (SAM) based on background removal by wavelet transform algorithm was investigated in this work. Five different kinds of certified reference soil samples (lead (Pb) concentrations were 110, 283, 552, 675, and 1141 ppm, respectively) were used to examine the accuracy of this method. The root mean square error of prediction (RMSEP) was more than 303 ppm by using the conventional calibration method. After adoption of SAM with background removal by wavelet transform algorithm, the RMSEP was reduced to 25.7 ppm. Therefore, the accuracy of the Pb element was improved significantly. The mechanism of background removal by wavelet transform algorithm based on SAM is discussed. Further study demonstrated that this method can also improve the predicted accuracy of the Cd element.

Notch Signaling in Pancreatic Development

The Notch signaling pathway plays a significant role in embryonic cell fate determination and adult tissue homeostasis. Various studies have demonstrated the deep involvement of Notch signaling in the development of the pancreas and the lateral inhibition of Notch signaling in pancreatic progenitor differentiation and maintenance. The targeted inactivation of the Notch pathway components promotes premature differentiation of the endocrine pancreas. However, there is still the contrary opinion that Notch signaling specifies the endocrine lineage. Here, we review the current knowledge of the Notch signaling pathway in pancreatic development and its crosstalk with the Wingless and INT-1 (Wnt) and fibroblast growth factor (FGF) pathways.

Tissue culture characteristics of maize (Zea mays L.) haploid coleoptile sections

Doubled haploid (DH) technology, which is used for rapidly purifying genetic resources, is a key technology in modern maize breeding. The present study evaluated the tissue culture characteristics of maize haploid coleoptile sections, in order to provide a new way of haploid doubling. With 20 combinations of haploid coleoptile sections, obtained by hybridization within Reid, Tangsipingtou, and Term-tropical groups, as explants, we analyzed the induction and differentiation rate of callus, observed the number of root tip chromosomes in regenerated plants, and analyzed the pollen fertility. In addition, we used 47 SSR markers to analyze the genotypes of regenerated plants. The Reid and Tangsipingtou groups had significantly higher induction rates of haploid coleoptile callus compared to the Term-tropical group. Fifteen haploid plants were obtained which had 10 chromosomes in the root tips as assessed by I-KI staining. It was also noticed that the pollen of pollinated anthers were partially fertile. The haploid plants had genetic stability and showed no variation. The Reid and Tangsipingtou groups had good culture characteristics of haploid coleoptile sections, while the Term-tropical group had poor culture characteristics. Genotypes of haploid plants generated by tissue culture were evidenced to come from recombinant types of parents. Thus, this study established a tissue culture system of maize haploid coleoptile.

Weak cation magnetic separation technology and MALDI-TOF-MS in screening serum protein markers in primary type I osteoporosis

We investigated weak cation magnetic separation technology and matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS) in screening serum protein markers of primary type I osteoporosis. We selected 16 postmenopausal women with osteoporosis and nine postmenopausal women as controls to find a new method for screening biomarkers and establishing a diagnostic model for primary type I osteoporosis. Serum samples were obtained from controls and patients. Serum protein was extracted with the WCX protein chip system; protein fingerprints were examined using MALDI-TOF-MS. The preprocessed and model construction data were handled by the ProteinChip system. The diagnostic models were established using a genetic arithmetic model combined with a support vector machine (SVM). The SVM model with the highest Youden index was selected. Combinations with the highest accuracy in distinguishing different groups of data were selected as potential biomarkers. From the two groups of serum proteins, 123 cumulative MS protein peaks were selected. Significant intensity differences in the protein peaks of 16 postmenopausal women with osteoporosis were screened. The difference in Youden index between the four groups of protein peaks showed that the highest peaks had mass-to-charge ratios of 8909.047, 8690.658, 13745.48, and 15114.52. A diagnosis model was established with these four markers as the candidates, and the model specificity and sensitivity were found to be 100%. Two groups of specimens in the SVM results on the scatterplot were distinguishable. We established a diagnosis model, and provided a new serological method for screening and diagnosis of osteoporosis with high sensitivity and specificity.

Eosinophil cationic protein mRNA expression in children with bronchial asthma

Studies have shown that eosinophils are closely related to pathogenesis of bronchial asthma. Eosinophils release eosinophil cationic protein (ECP), which plays an important role in infection and allergic reactions. Serum ECP mRNA expression in children with bronchial asthma has not been adequately investigated. We analyzed serum ECP mRNA expression in 63 children with bronchial asthma and 21 healthy children by using reverse-transcriptase polymerase chain reaction to understand the role of ECP in children with bronchial asthma. The children with bronchial asthma were segregated into acute-phase and stable-phase groups, based on the severity of the illness. Serum ECP mRNA expression in children with bronchial asthma (0.375 ± 0.04) was significantly higher than that in healthy controls (0.20 ± 0.02; P < 0.05). Additionally, children in the acute-phase group showed higher ECP mRNA expression level (0.44 ± 0.06) than those in the stable-phase (0.31 ± 0.03) and healthy control groups (0.20 ± 0.02; P < 0.05), while the level in the stable-phase (0.31 ± 0.03) was markedly higher than that in the healthy control group (0.20 ± 0.02; P < 0.05). Detection of serum ECP mRNA expression level has possible applications in the diagnosis and treatment of children with bronchial asthma.

15-Deoxy-prostaglandin J2 anti-inflammation in a rat model of chronic obstructive pulmonary disease and human bronchial epithelial cells via Nrf2 activation

Nuclear factor-erythroid 2-related factor 2 (Nrf2) is a transcription factor that regulates antioxidant and anti-inflammatory genes, and it plays a crucial role in the pathogenesis of chronic obstructive pulmonary disease (COPD). Moreover, 15-deoxy-delta12,14-prostaglandin J2 (15d-PGJ2) plays a protective role against oxidative stress and inflammation both in vivo and in vitro. In a previous study, we found that 15d-PGJ2 increased the expression of Nrf2 in a COPD rat model. This study aims to elucidate the role of 15d-PGJ2 in COPD pathogenesis and the relationship between Nrf2 and human bronchial epithelial (HBE) cells. Normal HBE (HBE) cells were cultured. Following cigarette smoke extract (CSE) stimulation, pre-incubation with or without small interfering RNA (siRNA) Nrf2, and stimulation with or without 15d-PGJ2, the expression levels of Nrf2, NF-κBp65, and IL-8 were detected by reverse transcription-polymerase chain reaction and western blot, respectively. The expression of NF-κBp65 and IL-8 in CSE-stimulated normal HBE cells was inhibited by 15d-PGJ2 at both the mRNA level and the protein level. Moreover, the expression of Nrf2 in normal HBE cells was improved by 15d-PGJ2 at both the mRNA level and the protein level. However, the inhibitory or improving effects of 15d-PGJ2 were disengaged by siRNA Nrf2 at both the mRNA level and the protein level. 15d-PGJ2 possesses anti-inflammatory properties in the pathogenesis of COPD, and HBE cells stimulated by CSE via Nrf2 activation.

Losartan improves the distribution and efficacy of doxorubicin in CT26 tumor

OBJECTIVE

The effectiveness of chemotherapeutic agents is impaired by limited delivery of chemotherapeutic agents to the tumor cells. Improving drug penetration in tumor tissues is very important. We tested whether losartan, a selective antagonist against type 1 angiotensin II receptors (AT1R) with noted antifibrotic activity, can enhance the penetration and efficacy of doxorubicin.

MATERIALS AND METHODS

BALB/C mice, which implanted with CT26 tumor cells, were divided into four groups: control, doxorubicin alone, losartan alone and doxorubicin + losartan combination groups. At day 0, the losartan alone and doxorubicin + losartan combination groups received losartan; and at day 8, the doxorubicin alone and doxorubicin + losartan combination groups received doxorubicin i.v. Tumor growth and intratumoral distribution of doxorubicin were evaluated. The mechanism underlying the enhanced anti-tumor effect of the combination of doxorubicin and losartan was investigated by immunohistochemical analysis.

RESULTS

Treatment with losartan alone did not suppress tumor growth; In contrast, treatment with doxorubicin alone decreased tumor growth; losartan and doxorubicin were administered in combination, had a synergistic effect that the tumor growth was much more inhibited. The decreased proliferation as indicated by down-regulation of Ki67, and increased apoptosis as indicated by TUNEL and caspase-3 staining. The expression of tumor suppressor gene P53 increased in doxorubicin + losartan combination groups.

CONCLUSIONS

Losartan can increase the therapeutic effectiveness of doxorubicin, yielding more great antitumor benefit. This study provided a rationale for initiating clinical trials using losartan in combination with chemotherapeutic agents to increase their therapeutic effectiveness.

A follow-up study on acute respiratory distress syndrome survivors after extracorporeal membrane oxygenation by pulmonary high-resolution CT

OBJECTIVE

This study aims to identify morphological changes in the lung parenchyma of acute respiratory distress syndrome (ARDS) survivors after extracorporeal membrane oxygenation  (ECMO) by high-resolution computed tomography (HRCT) follow-up. Factors influencing these changes are also examined.

METHODS

Information and lung HRCT scans were collected and studied 1, 3, 6, and 12 months after the withdrawal of severe ARDS survivors rescued by ECMO in the Respiratory Care Unit of Beijing Chaoyang Hospital from November 2009 to August 2012. The observation endpoint was set as the time when the lung lesions were basically absorbed or 12 months after withdrawal.

RESULTS

Among nine survivors, one survivor was lost to follow-up. The lesions of two patients, which were attributed to bacterial pneumonia and pneumocystis pneumonia, were basically absorbed 1 month after surgery. Six patients completed the 12 month follow-up. Although initial morphological changes varied, different degrees of absorption improvement were observed in later stages of treatment. Lung HRCT analysis on the sixth month indicated that the degree of involvement of the ventral region was greater than that of the dorsal area. No significant difference was observed in patients in terms of ECMO support time, pre-ECMO Murray score, and APACHE II score, among others.

CONCLUSION

Lung HRCT of severe ARDS survivors after ECMO treatment showed various degrees of morphological changes in the lung parenchyma. The severity of these changes may be associated with the disease duration.

Salinity-dependent toxicities of zinc oxide nanoparticles to the marine diatom Thalassiosira pseudonana

This study comprehensively investigated the influences of salinity, exposure concentration and time on the aggregate size, surface charge and dissolution of zinc oxide nanoparticles (ZnO-NPs; 20nm) in seawater, and examined the interacting effect of salinity and waterborne exposure of ZnO-NPs on the marine diatom Thalassiosira pseudonana for 96h. We found that aggregate sizes of ZnO-NPs significantly increased with increasing salinity, but generally decreased with increasing exposure concentration. Ion release decreased with increasing salinity, whereas the surface charge of the particles was not affected by salinity. The increased aggregate size and decreased ion release with increasing salinity, and consequently lower concentration of bioavailable zinc ions, resulted in decreased toxicity of ZnO-NPs at higher salinity in general in terms of growth inhibition (IC50) and chlorophyll fluorescence (EC50 - ФPo and EC50 - Ф2). However, IC50s and EC50s of ZnO-NPs were smaller than those of Zn(2+) (from ZnO-NPs ultrafiltrate and ZnCl2), indicating that dissolved Zn(2+) can only partially explain the toxicity of ZnO-NPs. SEM images showed that ZnO-NPs attached on the diatom frustule surface, suggesting that the interaction between the nanoparticles and the cell surface may acerbate the toxicity of ZnO-NPs. Our results linked the physicochemical characteristics of ZnO-NPs in seawater with their toxicities to the marine diatom and highlighted the importance of salinity as an influential environmental factor governing the aggregation, dissolution and the toxicity of ZnO-NPs.

Scanning electron microscopy of antennal sensory organs of the cattle grub, Hypoderma lineatum (Diptera: Oestridae)

Hypoderma lineatum (Villers, 1789) (Diptera: Oestridae) is a hypodermosis fly that has resulted in great economic losses worldwide. The antennae of cattle grub males and females were examined through stereoscopic microscopy and scanning electron microscopy to reveal the general morphology, combined with distribution, type, size, and ultrastructure of the antennal sensilla. All of the three antennal segments (antennal scape, pedicel, and funiculus) possess microtrichiae on their surface. Mechanoreceptors only exist on the antennal scape and pedicel. The antennal funiculus presents four types of antennal sensilla: trichoid, basiconic, coeloconic, and clavate sensilla. Three distinctive characters of H. lineatum are obvious: (1) the relatively slender, flexible, and equal-height mechanoreceptors; (2) the enlarged antennal pedicel, and numerous antennal sensory pits and pit sensilla on the antennal funiculus; and (3) all types of antennal sensilla clustered in sensory pits, respectively. Additionally, the enlarged antennal pedicel and abundant sensory pits and pit sensilla might facilitate odor detection, enhance olfactory sensitivity and accuracy, and also protect the fragile antennal sensilla from mechanical irritation or damage.

Effects of lead contamination on the clonal propagative ability of Phragmites australis (common reed) grown in wet and dry environments

Clonal propagation is important for the survival and maintenance of the common reed Phragmites australis. Pot culture experiments were conducted to investigate the effects of lead (Pb) concentration (0, 500, 1500, 3000, 4500 mg·kg(-1) ) and water stress on the clonal reproductive ability of this species. The Pb concentration found in plant organs, in decreasing order, was roots >shoots >rhizomes. There was a negative relationship between the growth of clonal propagative modules (excluding axillary shoot buds) and Pb concentrations, which caused a decrease in biomass, rhizome growth and number of axillary and apical rhizome buds. Daughter axillary shoots exhibited a tolerance strategy, with no significant change in their number; the axillary and apical rhizome buds, daughter apical rhizome shoots and rhizomes exhibited compensatory growth during the late stage of Pb (excluding 4500 mg·kg(-1) ) treatment in a wet environment. Pb applications above 500 mg·kg(-1) reduced these parameters significantly in the drought treatment, except for the number of axillary shoot buds, which did not change. Our results indicate that clonal propagative resistance to Pb contamination can occur via tolerance strategies, compensatory growth and a Pb allocation strategy, enabling these reeds to maintain population stability in wet environments. However, clonal modular growth and reproductive ability were inhibited significantly by the interaction between drought and Pb, which would cause a decline in P. australis populations in a dry environment. Lead concentrations of 4500 and 500 mg·kg(-1) in soils might meet or exceed the Pb tolerance threshold of clonally propagated reeds in wet and dry environments, respectively.

Cost-effective sampling of (137)Cs-derived net soil redistribution: part 2 - estimating the spatial mean change over time

The caesium-137 ((137)Cs) technique for estimating net, time-integrated soil redistribution by the processes of wind, water and tillage is increasingly being used with repeated sampling to form a baseline to evaluate change over small (years to decades) timeframes. This interest stems from knowledge that since the 1950s soil redistribution has responded dynamically to different phases of land use change and management. Currently, there is no standard approach to detect change in (137)Cs-derived net soil redistribution and thereby identify the driving forces responsible for change. We outline recent advances in space-time sampling in the soil monitoring literature which provide a rigorous statistical and pragmatic approach to estimating the change over time in the spatial mean of environmental properties. We apply the space-time sampling framework, estimate the minimum detectable change of net soil redistribution and consider the information content and cost implications of different sampling designs for a study area in the Chinese Loess Plateau. Three phases (1954-1996, 1954-2012 and 1996-2012) of net soil erosion were detectable and attributed to well-documented historical change in land use and management practices in the study area and across the region. We recommend that the design for space-time sampling is considered carefully alongside cost-effective use of the spatial mean to detect and correctly attribute cause of change over time particularly across spatial scales of variation.

An efficient algorithm for computing fixed length attractors based on bounded model checking in synchronous Boolean networks with biochemical applications

Genetic regulatory networks are the key to understanding biochemical systems. One condition of the genetic regulatory network under different living environments can be modeled as a synchronous Boolean network. The attractors of these Boolean networks will help biologists to identify determinant and stable factors. Existing methods identify attractors based on a random initial state or the entire state simultaneously. They cannot identify the fixed length attractors directly. The complexity of including time increases exponentially with respect to the attractor number and length of attractors. This study used the bounded model checking to quickly locate fixed length attractors. Based on the SAT solver, we propose a new algorithm for efficiently computing the fixed length attractors, which is more suitable for large Boolean networks and numerous attractors' networks. After comparison using the tool BooleNet, empirical experiments involving biochemical systems demonstrated the feasibility and efficiency of our approach.

Ultrastructure of antennal sensory organs of horse nasal-myiasis fly, Rhinoestrus purpureus (Diptera: Oestridae)

Rhinoestrus purpureus (Brauer, 1858) (Diptera: Oestridae) is an economically important parasite that can cause severe nasal myiasis in equids or even attacking humans. The antennae of R. purpureus were examined using stereoscopic microscopy and scanning electron microscopy. The general morphology was provided detailedly, together with distribution, type, size, and ultrastructure of antennal sensilla. All the three antennal segments, antennal scape, pedicel, and funiculus, are interspersed by microtrichiae. Only mechanoreceptors are detected on antennal scape and pedicel. On antennal funiculus, three types of sensilla were observed, including basiconic sensilla, coeloconic sensilla and clavate sensilla. Two features are characterized of this host-specific bot fly: (1) numerous sensory pits with branched basiconic sensilla on antennal funiculus and (2) the absence of trichoid sensilla. The function of these distinctive traits are discussed in association with the life history. We suggest that more sensory pits with branched sensilla could increase the sensitivity of olfactory system for host orientation, while the capability of pheromone identification might be reduced due to the absence of trichoid sensilla. Besides, we support both thermo- and chemo-functions of coeloconic sensilla.

Acidity measurement of iron ore powders using laser-induced breakdown spectroscopy with partial least squares regression

Laser-induced breakdown spectroscopy (LIBS) with partial least squares regression (PLSR) has been applied to measuring the acidity of iron ore, which can be defined by the concentrations of oxides: CaO, MgO, Al₂O₃, and SiO₂. With the conventional internal standard calibration, it is difficult to establish the calibration curves of CaO, MgO, Al₂O₃, and SiO₂ in iron ore due to the serious matrix effects. PLSR is effective to address this problem due to its excellent performance in compensating the matrix effects. In this work, fifty samples were used to construct the PLSR calibration models for the above-mentioned oxides. These calibration models were validated by the 10-fold cross-validation method with the minimum root-mean-square errors (RMSE). Another ten samples were used as a test set. The acidities were calculated according to the estimated concentrations of CaO, MgO, Al₂O₃, and SiO₂ using the PLSR models. The average relative error (ARE) and RMSE of the acidity achieved 3.65% and 0.0048, respectively, for the test samples.

Nonlinear entanglement and its application to generating cat States

The Einstein-Podolsky-Rosen (EPR) paradox, which was formulated to argue for the incompleteness of quantum mechanics, has since metamorphosed into a resource for quantum information. The EPR entanglement describes the strength of linear correlations between two objects in terms of a pair of conjugate observables in relation to the Heisenberg uncertainty limit. We propose that entanglement can be extended to include nonlinear correlations. We examine two driven harmonic oscillators that are coupled via third-order nonlinearity can exhibit quadraticlike nonlinear entanglement which, after a projective measurement on one of the oscillators, collapses the other into a cat state of tunable size.

Ultrastructural investigation of antennae in three cutaneous myiasis flies: Melophagus ovinus, Hippobosca equina, and Hippobosca longipennis (Diptera: Hippoboscidae)

Melophagus ovinus (Linnaeus 1758), Hippobosca equina Linnaeus, 1758, and Hippobosca longipennis Fabricius, 1805 (Diptera: Hippoboscidae) are economically and medically important ectoparasites that can act as mechanic vectors of pathogens and cause myiasis in both human and domestic animals. As essential olfactory organs, antennae of these adult hippoboscids were examined using stereoscopic and scanning electron microscopes. General morphology of the antenna is provided in detail, combined with distribution, types, size, and ultrastructures of antennal sensilla. On the antennal funiculus, two types of sensilla are observed, including basiconic sensilla and coeloconic sensilla. Four common characters are shared among the three species: (1) the scape is either obsolete or fused with the fronto-clypeus; (2) branched antennal structures (branched pedicellar microtrichiae and branched arista with only one segment) are detected; (3) the enlarged antennal pedicel completely envelops the antennal funiculus; and (4) less types of sensilla on funiculus. Disparity and diversity of the antennal and sensory structures are analyzed from the phylogenetic and functional perspective. We suggest that hippoboscids are potential model for the study of the function of coeloconic sensilla in Calyptratae.

Underlying heart disease and microbiological spectrum of adult infective endocarditis in one Chinese university hospital: a 10-year retrospective study

BACKGROUND AND AIM

To identify the underlying heart disease and microbiological pathogen associated with infective endocarditis (IE) in Chinese patients in one university hospital over a 10-year period.

METHODS

We recruited 115 adult patients admitted to Peking University First Hospital from 2002 to 2011 who were diagnosed with definite IE. Statistical analysis was performed to analyse data on demographics, clinical and laboratory findings, as well as microbiological pathogens.

RESULTS

The most common underlying heart diseases for IE were congenital heart disease (24.3%) followed by degenerative valvular disease (17.4%). Aortic (44.3%) and mitral (43.5%) valves were most frequently affected. The right-sided IE cases were all found in patients with congenital heart disease. The age of patients was younger in right-sided cases than that in left-sided ones (P = 0.001). There was no difference in the mortality among groups with different underlying heart disease (P = 0.841). Forty-four (38.3%) patients were infected with viridans group streptococci. The isolation rate of staphylococci in right-sided IE was higher than that in the left-sided IE group (P = 0.021). More than 85% of streptococci were susceptible to β-lactams.

CONCLUSIONS

Congenital heart disease and degenerative valvular disease have overtaken rheumatic heart disease as the major underlying heart diseases associated with IE. Viridans group streptococci are the most common microbial cause of IE.

Double-resonance enhanced intersubband second-order nonlinear optical susceptibilities in GaN/AlGaN step quantum wells

Second-order nonlinear optical susceptibilities for second harmonic generation (SHG) associated with intersubband transitions in GaN/AlGaN single quantum well and step quantum well have been studied theoretically by solving Schrödinger and Poisson equations self-consistently. The calculated results suggest that due to the very large polarization-induced field in the quantum well, the potential profile becomes asymmetrical, leading to large second-order susceptibilities. A high value about 4 × 10^-7 m/V can be obtained in single quantum well structure. Furthermore, by adopting step quantum well structure to increase the asymmetry degree of the potential profile and manipulate the energy levels for double-resonance, a significant enhancement of second-order susceptibility can occur in step quantum well. Specifically, the susceptibility can be as large as 4 × 10^-6 m/V with structure optimization, about an order of magnitude greater than that in single quantum well. The results indicate that nonlinear optical elements based on GaN/AlGaN step quantum wells are very promising for SHG in a wide range of wavelengths from telecommunication to mid-infrared, especially effective in longer wavelength.

Accuracy improvement of quantitative analysis in laser-induced breakdown spectroscopy using modified wavelet transform

A modified algorithm of background removal based on wavelet transform was developed for spectrum correction in laser-induced breakdown spectroscopy (LIBS). The optimal type of wavelet function, decomposition level and scaling factor γ were determined by the root-mean-square error of calibration (RMSEC) of the univariate regression model of the analysis element, which is considered as the optimization criteria. After background removal by this modified algorithm with RMSEC, the root-mean-square error of cross-validation (RMSECV) and the average relative error (ARE) criteria, the accuracy of quantitative analysis on chromium (Cr), vanadium (V), cuprum (Cu), and manganese (Mn) in the low alloy steel was all improved significantly. The results demonstrated that the algorithm developed is an effective pretreatment method in LIBS to significantly improve the accuracy in the quantitative analysis.